Concept explainers
A space truss has three-dimensional pin supports at joints 0, B, and C, Load P is applied at joint A and acts toward point Q. Coordinates of all joints arc given in feet (see figure).
(a) Find reaction force components B x, B z, and Oz
(b) Find the axial force in truss member AC.
(a)
You need to determine the force components
Answer to Problem 1.3.13P
The forces are:
Explanation of Solution
Given Information:
You have following figure with all relevant information,
Draw free body diagram of joints and use equilibrium of forces to determine the unknowns.
Calculation:
Draw free body diagram as shown in the following figure,
Joint A :
The forces at joint A are,
Take equilibrium of forces at joint A in vector form,
The vector equation yields three equations in components form as below,
Solve the three equations to get
Joint O :
Consider the free body diagram again,
The forces at joint O are,
Take equilibrium of forces at joint O in vector form,
The vector equation yields three equations in components form as below,
Solve the equation (3) to get
Joint B :
Consider the free body diagram again,
The forces at joint B are,
Take equilibrium of forces at joint O in vector form,
The vector equation yields three equations in components form as below,
Solve the equation (3) to get
Conclusion:
Therefore the forces are:
(b)
You need to determine the member force
Answer to Problem 1.3.13P
The forces are:
Explanation of Solution
Given Information:
You have following figure with all relevant information,
Draw free body diagram of joints and use equilibrium of forces to determine the unknowns.
Calculation:
Draw free body diagram as shown in the following figure,
Joint A :
The forces at joint A are,
Take equilibrium of forces at joint A in vector form,
The vector equation yields three equations in components form as below,
Solve the three equations to get
Conclusion:
Therefore the member force in AC is:
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Chapter 1 Solutions
Mechanics of Materials (MindTap Course List)
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